JP2023510188A - Automatic role reversal prevention for dual roll ports - Google Patents

Abstract

Aspects of the present disclosure provide a circuit (102). In at least some examples, the circuit includes dual role ports (124) for transferring power to and from the circuit. The circuit also includes a microprocessing unit (114). The microprocessing unit controls the circuit to operate as a sink device for receiving power from the source device through the dual role port when the power supply includes a first amount of stored energy, and the terminating resistor of the source device. is detected at the dual-role port and controls the circuit to limit power transfer from the circuit to the power supply through the dual-role port when the power supply changes state from a sourcing state to a sinking state. configured to

Description

Universal Serial Bus (USB) communication occurs between a host with a downstream facing port (DFP) and a device with an upstream facing port (UFP). DFPs and UFPs are sometimes implemented by a single port called a dual role port (DRP) that can be controlled to operate as either a DFP or a UFP. In some USB technologies, such as USB Type C (USB-C), a single DRP port can both source and sink power. DRP ports dynamically or automatically role between DFPs or UFPs and/or between power sources or power sinks based automatically on one or more monitored conditions. It can also be changed. This dynamic or automatic change can sometimes be a drawback.

Various aspects of the disclosure provide a circuit. In at least some examples, the circuit includes dual role ports for transferring power to and from the circuit. The circuit also includes a microprocessing unit. The microprocessing unit controls the circuitry of the source device to operate as a sink device for receiving power from the source device via the dual role port when the power supply includes a first amount of stored energy. To detect changes in termination resistance at the dual role port and to limit power transfer from the circuit to the power supply through the dual role port when the power supply changes state from sourcing to sinking. is configured to control the circuit to

Another aspect of the disclosure provides a system. In at least one example, the system includes a power bank configured to act as the source device. The power bank includes a battery, dual role bus voltage terminals for transferring power to and from the battery, and a microprocessing unit. The microprocessing unit controls the battery to source power to the sink device via the dual role bus voltage terminals when the battery contains the first amount of stored energy and the battery receives the first amount of energy. is configured to inhibit power transfer from the sink device to the battery through the dual role port when the sink device contains less energy than the stored energy of the dual role port.

Another aspect of the disclosure provides a computer program product including a computer-readable storage medium containing program instructions. In at least one example, the program instructions cause a device communicatively coupled to the microprocessing unit to receive power from the source device via a dual role port capable of non-concurrent operation as both an input terminal and an output terminal. so that the source device can operate the source device and the dual role port on the source side of the communication channel while the source device is outputting power. Terminate the communication channel coupled to the pull-up signal. Executing the program instructions further causes the microprocessing unit to detect removal of the pullup signal on the source side of the communication channel and start a timer when the removal of the pullup signal is detected. Executing the program instructions further causes the microprocessing unit to detect that the pull-down signal terminates communication on the source side of the communication channel, and that the pull-down signal terminates communication on the source side of the communication channel causes the timer to expire. inhibit power transfer to the source device through the dual role port when detected before

Reference is now made to the accompanying drawings for a detailed description of various examples.

1 illustrates a block diagram of an exemplary Universal Serial Bus (USB) system, in accordance with various examples; FIG.

4 illustrates a flowchart of an example method for controlling power transfer, in accordance with various examples.

4 shows an exemplary pseudo-code table for implementing power transfer, in accordance with various examples.

4 illustrates a flowchart of an example method for controlling power transfer, in accordance with various examples.

4 illustrates a flowchart of an example method for controlling power transfer, in accordance with various examples.

4 shows an exemplary pseudo-code table for implementing power transfer, in accordance with various examples.

4 illustrates a flow chart of an example method for power transfer, in accordance with various examples.

In this disclosure, a source device is a device with a finite source of power that discharges to charge another device (e.g., a power bank with rechargeable batteries, a portable computing device with rechargeable batteries, etc.) point to Further in this disclosure, a sink device refers to a device that couples to a source device to receive power from the source device for operating and/or charging the sink device. The source and sink devices each have the ability to reverse roles (eg, source acting as sink and vice versa). When a source device, such as a rechargeable battery pack (e.g., power bank), is electrically coupled to a sink device, such as a mobile phone, tablet device, wearable device, portable computer, etc., it is often stored within the source device. It is intended that the supplied power be used to charge the sink device. Wasted energy can occur, such as in the form of transmission losses, and can be counterproductive to the desired results of charging if the source and sink devices reverse roles during charging.

When the source device and sink device are each a Universal Serial Bus (USB) Type-C (USB-C) device that utilizes dual role ports (DRP), the ports assume roles based on the charge status of the source and sink devices. can be dynamically reversed. For example, power passes from the source device to the sink device when the source device is coupled to the sink device and is storing more charge than the sink device. During this time, the source device is in the sourcing state or operating mode. When the power stored by the source device is consumed, in at least some instances the source device presents itself as a sink device (eg, to an initial sink device, etc.). During this time, the source device is now in sinking state or operating mode. The DRP's dynamic role reversal capability allows the sink device to begin recharging the battery of the source device when the sink device enters the sourcing state or operating mode. This role reversal is undesirable because, in at least some situations, energy is lost due to heat and other transfer-related losses, reducing the amount of power available for further charging. In some situations, the sink device that the user is attempting to charge by coupling the source device to the sink device is charged and then discharged again, leaving the user little or no additional time to use the sink device. This role reversal is even less desirable, as there may be no For example, if a user couples an external rechargeable battery to a laptop computer via the DRP, the laptop computer's internal rechargeable battery may be charged based on the energy received from the external rechargeable battery. Charging stops when little or no energy remains in the external rechargeable battery. However, the laptop computer then sees the discharged external rechargeable battery as a device for charging, similar to if a discharged mobile phone were coupled to the laptop computer. Thus, the laptop computer can automatically initiate the transfer of energy from the internal rechargeable battery to the external rechargeable battery. In the absence of a user to observe this automatic role change, such as when charging is unattended, the internal and external rechargeable batteries may continue to transfer energy back and forth. In at least some instances, this role reversal can continue until all available energy has been consumed due to losses and there is no energy left to charge or operate the laptop computer. ,Repeated. Therefore, in at least some situations, it is desirable to prevent automatic role reversal of DRPs in source and/or sink devices.

At least some aspects of the present disclosure provide mechanisms for automatic role reversal of DRPs. Additionally, at least some aspects of the present invention otherwise inhibit power transfer from a sink device to a source device from which the sink device received power. Some implementations are at least partially mechanical, such as through plugging and re-plugging of switches, buttons, or bonds. For example, when the switch is in the first position, the DRP is controlled to source power but not sink power. When the switch is in the second position, the DRP is controlled to sink power but not source power. The switch is actuated by the user based on the user's desired DRP behavior at a given time. Therefore, the mechanical implementation of the present disclosure requires some form of user input. Alternatively, role reversal is prevented until the coupling between the two devices is separated and later recoupled. Other implementations can be implemented at least partially through software. For example, software implementations are timer-based. In other examples, the software implementation is based on one or more alerts or messages that warn of an impending role reversal of the DRP and allow the user to provide input to allow or deny the DRP's role reversal. . In at least some examples, the software implementation further utilizes user input, such as preventing role reversal until the user provides user input that commands operation in the sourcing mode.

Turning now to FIG. 1, a block diagram of an exemplary USB system 100 is shown. In one example, the USB system includes source device 102 , USB cable 104 and sink device 106 . In at least one example, source device 102 is a device that provides signals to sink device 106 via USB cable 104 , and sink device 106 pulls current from source device 102 via USB cable 104 . It's becoming In some examples, at least a portion of the current received by sink device 106 from source device 102 is stored by sink device 106 in a battery (not shown) such that the battery is charged. In some implementations, source device 102 includes power supply 108 , USB power carrier (PD) controller 110 , and voltage control circuitry 112 . Power supply 108 is, for example, a power supply capable of providing an output signal with an adjustable voltage level that is adjusted based on control signals received by power supply 108 . In at least some examples, power supply 108 is or includes a rechargeable battery.

Power supply 108 receives a control signal from voltage control circuit 112 . In some examples, power supply 108 receives control signals from voltage control circuit 112 via optical communication (eg, an optocoupler). In another example, power supply 108 receives control signals from voltage control circuit 112 via a physical coupling between power supply 108 and voltage control circuit 112 . In yet another example, power supply 108 itself is not adjustable, but an external component coupled or configured to be coupled to the output of power supply 108 changes the value of the signal output by power supply 108 . adjust the For example, the output of power supply 108 may be a signal having a substantially constant voltage value that outputs one or more other signals having different voltage values than the output of power supply 108. is operated to For example, the output of power supply 108 may be manipulated by a power converter (not shown), such as a buck converter, boost converter, or buck-boost converter, and the output of the power converter may be provided to node 118 . In at least some examples, the power converter is controlled by voltage control circuit 112 to manipulate the output of power supply 108 to form one or more other signals. In at least one example, USB PD controller 110 is a microcontroller with processing power. In other examples, USB PD controller 110 receives one or more inputs and generates one or more outputs based on rules, analysis, or other processing applied to at least some of the inputs. Any processing element capable of producing output.

Voltage control circuit 112 is any circuit capable of regulating and/or controlling the value of the signal present at node 118 . For example, voltage control circuit 112 receives a reference voltage (VREF) from USB PD controller 110 and controls power supply 108 according to VREF to control the value of the bus voltage (VBUS) signal present at node 118 . is any circuit capable of For example, voltage control circuit 112 may be used to cause the signal present at node 118 to be approximately equal, proportional, or otherwise related to the value of VREF, the range of which is not limited herein. , VREF to control the power supply 108 .

USB PD controller 110 includes and/or implements at least a portion of microprocessing unit 114 in at least some examples. In various examples, microprocessing unit 114 is a processor, microprocessor, field programmable gate array (FPGA), a component suitable or capable of implementing a state machine, or Any other suitable component or device having processing capabilities. For example, when USB PD controller 110 is a microcontroller, at least a portion of microprocessing unit 114 is specified within USB PD controller 110 to perform at least some of the operations disclosed herein. implemented as programming. For example, microprocessing unit 114 executes or implements software or other code to prevent automatic role reversal of DRP ports of source device 102 . The DRP port is the VBUS terminal 122 in at least one example. For example, VBUS terminal 122 may be a DRP port capable of providing power to sink device 106 via USB cable 104 or receiving power from sink device 106 via USB cable 104 . In some examples, source device 102 includes a transistor 116 operable as a switch to control the output of the VBUS signal through VBUS terminal 122 and a plug to provide communicative coupling with source device 102 . and a receptacle 124 configured to receive it. Transistor 116 can be of any suitable technology, including at least a p-type field effect transistor (FET) or an n-type FET.

In at least one exemplary architecture, the output of power supply 108 is coupled to node 118 and the input of voltage control circuit 112 is coupled to node 118 . A first terminal of microprocessing unit 114 is coupled or configured to be coupled to node 118 and a first terminal (drain terminal) of transistor 116 is coupled to node 118 . A first input of voltage control circuit 112 is coupled to the VREF output of USB PD controller 110 and a first output of voltage control circuit 112 is coupled to the cathode (CATH) input of USB PD controller 110 . A first terminal of USB PD controller 110 is coupled to the gate terminal of transistor 116, a second terminal of USB PD controller 110 is coupled to node 120, and a second terminal (eg, source terminal) of transistor 116 is coupled to node 116. 120 and VBUS terminal 122 is coupled to node 120 . A second terminal of microprocessing unit 114 is configured to couple to configuration channel (CC) 1 terminal 132 and a third terminal of microprocessing unit 114 is configured to couple to CC2 terminal 134 . In various examples, CC1 and CC2 are each coupled to a connection voltage (VCONN) terminal 138 of USB cable 104 or a CC terminal 136 of USB cable 104, depending on the orientation in which plug 126 is inserted into receptacle 124. Configurable. In some examples, VBUS terminal 122, CC1 terminal 132, and CC2 terminal 134 are housed within or part of receptacle 124 to communicatively couple source device 102 to USB cable 104. or otherwise interact with receptacle 124 .

In at least one example, USB cable 104 includes plug 126 configured to interact with receptacle 124 to communicatively couple USB cable 104 to source device 102 . Plug 126 houses, includes, or otherwise includes VBUS terminal 140, CC terminal 136, and VCONN terminal 138, each configured to communicatively couple USB cable 104 to source device 102. interact with them.

Sink device 106 is any device suitable for coupling to USB cable 104 to receive power from source device 102 and/or to communicate data with source device 102, the range of sink device 106; Its hardware architecture, or its mode of operation, is not limited herein. In at least some examples, sink device 106 also implements a USB controller substantially similar to USB PD controller 110 and/or includes functionality substantially similar to microprocessing unit 114 .

In one example of the operation of system 100, after source device 102 (eg, USB PD controller 110) determines that sink device 106 is connected to source device 102 via USB cable 104, USB PD controller 110: Power supply 108 is controlled to output a signal having a voltage level specified by a control signal received by power supply 108 . USB PD controller 110 controls power supply 108 to output a signal, for example, by controlling voltage control circuit 112 .

In at least some examples, USB PD controller 110 applies pull-up signals to both CC1 terminal 132 and CC2 terminal 134 and monitors the value of the signal present on each of CC1 terminal 132 and CC2 terminal 134 . In some examples, the pullup signals are applied by coupling CC1 terminal 132 and CC2 terminal 134 to voltage supply 150 via pullup termination resistors (Rp) 142 . In at least some examples, voltage supply 150 outputs a signal having a different voltage value than power supply 108 . For example, in at least some implementations, voltage supply 150 outputs a signal having approximately 5V, approximately 3.3V, or another suitable voltage. The voltage of the signal output by voltage supply 150 is, in some examples, the signal output by power supply 108 (e.g., the output of power supply 108 as an input to generate the voltage provided by voltage supply 150). output of the receiving regulator or converter). In some examples, each of the pullup signals has substantially the same voltage level. In another example, each of the pullup signals has a different voltage level. For example, the USB PD controller 110 compares the value of the signal present on each of the CC1 terminal 132 and the CC2 terminal 134 to a threshold value to determine the value of the pull-up signal (or some proportion of the value of the pull-up signal). quantity). In various implementations, source device 102 monitors CC1 terminal 132 and/or CC2 terminal 134 for the presence of an open state, an Rd attached state, or an Ra attached state. An open condition exists for a CCx terminal (eg, either CC1 terminal 132 or CC2 terminal 134) when the value of the signal present at that CCx terminal exceeds a first threshold (1.6V in one example). . The Rd attached state exists for a CCx terminal when the signal present at that CCx terminal is below a first threshold and above a second threshold (0.25V in one example). The Rp attached state exists for a CCx terminal when the signal present at that CCx terminal is below a second threshold. In at least some examples, a CCx or CCy terminal (e.g., either CC1 terminal 132 or CC2 terminal 134 that is not the CCx terminal) determined to be in the Rd attached state is coupled to ground node 152. Terminated by a sink device 106 with a pull-down termination resistor (Rd).

In some examples, USB PD controller 110 ignores the presence of USB cable 104 when sink device 106 is not coupled to USB cable 104 (and thereby source device 102). For example, when the CCx terminal is in the Ra attached state and the CCy terminal is in the open state, USB PD controller 110 ignores the presence of USB cable 104 and does not communicate with USB cable 104 . In another example, USB PD controller 110 communicates with USB cable 104 when CCx terminal is in the Ra attached state and CCy terminal is in the open state (such as when USB cable 104 includes an electronic marker).

In at least some examples, when USB PD controller 110 detects the presence of sink device 106, USB PD controller 110 signals VBUS terminal 122, for example, by controlling power supply 108 to output VBUS. is applied. In some examples, USB PD controller 110 detects the presence of sink device 106 in one of two ways. First, USB PD controller 110 determines that sink device 106 is coupled to source device 102 when the CCx terminal is in the Rd attached state and the CCy terminal is in the open or Ra attached state. Second, the USB PD controller 110 also determines that the sink device 106 is coupled to the source device 102 when the CCx terminal is in the open or Ra attached state and the CCy terminal is in the Rd attached state. USB PD controller 110 determines, in at least some examples, that a CCx or CCy terminal is in the Rd attached state based on USB PD controller 110 terminating the CCx or CCy terminal with Rp 142 . USB PD controller 110 terminates the CCx or CCy terminals at Rp 142 by controlling switches 144 and 146 to couple the CCx and CCy terminals to Rp 142 . In at least some examples, switch 144 and switch 146 are each controlled by microprocessing unit 114 .

Similarly, when source device 102 is coupled to sink device 106 (e.g., via USB cable 104 using plug 126 and receptacle 124), sink device 106 has CC1 terminal 132 coupled to CC terminal 136. or load or pull down any of the CC2 terminals 134 (eg, through an approximately 5.1 kilohm resistor, etc.). Pulling down one of CC1 terminal 132 or CC2 terminal 134 reduces the value of the signal present on one of CC1 terminal 132 or CC2 terminal 134 coupled to CC terminal 136, causing one of CC1 terminal 132 or CC2 terminal 134 to decrease in value. to the Rd attached state.

Microprocessing unit 114 controls the provision of VBUS to VBUS terminal 122 in at least some examples. For example, microprocessing unit 114 controls transistor 116 to couple node 118 to VBUS terminal 122 . When power supply 108 is discharged, microprocessing unit 114 toggles switch 144 and switch 146 to couple the CCx or CCy terminal to pull-down termination resistor (Rd) 148 . When sink device 106 performs a toggle from Rd to Rp and assumes that the CCx or CCy terminal of source device 102 is terminated with Rd 148, sink device 106 becomes the new source device and source device 102 becomes the new Transition to become a sink device. However, in at least some examples, the microprocessing unit 114 outputs a signal indicating that the source device 102 and the sink device 106 should not reverse roles (e.g., a small portion or composition of a PD message or an alert message). element) to sink device 106 . When sink device 106 receives a signal indicating that it should not reverse roles with source device 102, in at least some examples, sink device 106 detects a disconnection of Rp at source device 102. implement a timer for Subsequently, if sink device 106 detects Rd on source device 102 before the expiration of the timer, sink device 106 does not reverse roles and becomes the new source device. However, if sink device 106 detects Rd on source device 102 after the timer expires, sink device 106 reverses roles and becomes the new source device, providing power to source device 102 acting as the new sink device. .

In another example, when the microprocessing unit 114 determines that the power level of the power supply 108 is at or below a predefined threshold, the microprocessing unit 114 communicates an alert or other message to the sink device 106. . The predefined threshold may be a percentage of maximum charge of power supply 108, such as approximately 10% maximum charge residual, 5% maximum charge residual, or any other predefined threshold. An alarm is, for example, notification of a charge drop in power supply 108 . In at least some examples, the alert further includes one or more interactive elements that may cause the user to provide feedback. For example, interactive elements include an option to allow role reversal of source device 102 and sink device 106 or an option to prevent role reversal of source device 102 and sink device 106 . In at least some examples, if the user does not respond to the alert within a predefined time period, the user's inactivity is assumed to be a negative response, and role reversal of source device 102 and sink device 106 is prevented. will be

In yet another example, source device 102 includes hardware switch 154 . Hardware switch 154 disconnects Rd in at least some instances so that the CCx or CCy terminals are not terminated by either Rp 142 or Rd 148 when power supply 108 is exhausted. In such an example, the user activates hardware switch 154 to prevent source device 102 from terminating the CCx or CCy terminals on Rd. This termination prevention, in at least some examples, serves for sink device 106 to detect termination of Rd 148 by source device 102 and to source power back from sink device 106 to source device 102. to prevent reversing. In at least some examples, based on the state (e.g., activated or not activated) of hardware switch 154, microprocessing unit 114 controls switch 156 to isolate Rd 148 from switches 144 and 146. do.

In yet another example, when sink device 106 detects removal of the termination of Rp 142 by source device 102, sink device 106 starts a timer. In some examples, the timer starts with a non-zero value, counts down toward zero, and expires when the count reaches zero. In another example, the timer starts at zero, counts up, and expires when the count reaches a predefined non-zero value. When the sink device 106 starts the timer, the sink device disables the dual role capability of the sink device 106 . If sink device 106 detects termination of Rd 148 by source device 102 before the expiration of the timer, sink device 106 keeps the dual role capability disabled. For example, the dual role functionality remains disabled until user input is received instructing sink device 106 to operate as a source device, or until Rd 148 is no longer terminated by source device 102 . If sink device 106 detects termination of Rd 148 by source device 102 after the timer expires, sink device 106 re-enables the dual role capability to source power to source device 102 currently operating in sinking mode. to start operating in sourcing mode.

Although discussed above as preventing power transfer between sink device 106 and source device 102, in at least some other examples power transfer is suppressed. In some examples, power transfer is completely prevented when power transfer is suppressed. In another example, when power transfer is throttled, power transfer is allowed but at a reduced rate. For example, when power transfer is throttled, the power transfer rate is lower than when power transfer is not throttled.

Although CC1 terminal 132 is configured to be coupled to CC terminal 136 and CC2 terminal 134 is configured to be coupled to VCONN terminal 138, discussed herein and shown in FIG. In the example these bonds are reversed. For example, at least some USB cables 104 are reversible such that CC1 terminal 132 couples to one of CC terminal 136 or VCONN terminal 138, depending on the orientation in which plug 126 is inserted into receptacle 124. , and CC2 terminal 134 is configured to couple to the other of CC terminal 136 or VCONN terminal 138 . Thus, although coupling associated with one orientation of insertion of plug 126 into receptacle 124 is described herein, any orientation of insertion of plug 126 into receptacle 124 is described herein. Associated couplings are contemplated and encompassed within the scope of this disclosure. Thus, in at least some examples, USB PD controller 110 determines which of CC1 terminal 132 or CC2 terminal 134 is coupled to node 118 to determine whether CC1 terminal 132 or CC2 terminal 134 is coupled to node 118 . It is further configured to detect and/or determine if it is coupled to VCONN terminal 138 (or CC terminal 136).

Turning now to FIG. 2, a flowchart of an exemplary method 200 for controlling power transfer is shown. In at least some examples, the method 200 initially receives power from a first device operating as a source device, but later operates as a sink device that can change roles and operate as a source device. 2, implemented by a microprocessing unit, such as microprocessing unit 114 . In at least some particular examples, method 200 is implemented by a microprocessing unit, such as microprocessing unit 114, implemented within a sink device, such as sink device 106, each of which was discussed above with respect to FIG.

At operation 202, the second device determines that Rp is no longer detected. For example, the second device determines that Rp is no longer detected when the first device ceases to have Rp present on the CC line coupling the first and second devices. In some examples, it is determined that Rp no longer exists by comparing the value of the voltage present on the CC line to a threshold. For example, when Rp is present, the voltage present on the CC line exceeds the threshold. When Rp is not present, the voltage present on the CC line is less than threshold. In at least some examples, no longer detected Rp indicates that power is no longer being delivered by the first device to the second device.

In operation 204, the second device detects the presence of Rd on the CC line coupling the first and second devices. In some examples, the presence of Rd is determined by comparing the value of the voltage present on the CC line to a threshold. For example, when Rd is present, the voltage present on the CC line may be between a pair of thresholds. When Rd is not present, the voltage present on the CC line may be outside a pair of thresholds. When Rd is not detected, the method remains at operation 206 . In at least some implementations, the presence of Rd on the CC line indicates that the first device is acting as a sink device. When the second device detects Rd on the CC line, in at least some instances, the second device starts sourcing power back to the first device. However, as previously described herein, such actions may result in undesirable operation of the first and second devices. Therefore, the second device proceeds to operation 206 before the second device sources power to the first device.

In operation 206, the second device determines whether Rd has been detected within a predetermined time period in which Rp is no longer detected. For example, when Rd is detected within a predetermined time period in which Rp is no longer detected, this may indicate that the first device has been discharged but remains coupled to the second device. In such instances, when the first and second devices are coupled via the DRP, undesirable reverse transfer of charge from the second device to the first device can occur. For example, when the power supply of the first device discharges, in some examples the terminal of the first device is terminated by Rd. This termination occurs within about 10 milliseconds (ms) in at least some instances. In another example, termination occurs between about 10ms and about 100ms. When a first device is disconnected from a second device and then reconnected to the second device, the terminals of the first device are still terminated by Rd. However, the physical action of separating and reconnecting the first and second devices can exceed the amount of time spent terminating the terminals of the first device when the first device's power supply is discharged. have a nature. For example, the physical action of separating and reconnecting the first and second devices may take about 100 ms or more. In this way, the second device is powered to the first device with the power supply discharged but the first device is not isolated from the second device, and the device to which the second device is newly coupled. can be distinguished from a device that is coupled to a second device with the intention of sourcing the

When Rd is detected within the predetermined time period, method 200 proceeds to operation 208 . In at least some examples, determining whether Rd is detected within a predetermined time period includes starting or otherwise initiating a counter or timer when Rp is no longer detected in operation 202. include. When Rd is detected in operation 204, the value of the counter or timer is compared to a timer threshold to determine if the timer value exceeds the timer threshold. In at least some examples, the timer threshold is configurable. For example, the timer threshold is configured to expire after approximately 10 ms, approximately 50 ms, approximately 100 ms, approximately 200 ms, or any other suitable amount of time.

In operation 308, the second device disables the DRP functionality of the second device. In at least some examples, disabling the DRP function means that the second device has Rp present on the CC line when the first device has Rd present on the CC line. , from starting operation as a source device to recharge the first device. Alternatively, in at least some examples, instead of disabling the DRP feature in operation 208, the second device limits the allowable rate of power transfer such that power transfer is inhibited, but not completely prevented. .

At operation 210, the second device determines whether the user wants the second device to act as the source device. The second device, in at least some examples, makes decisions based on input received from the user. In some examples, input is received via physical, articulable input sources such as switches, toggles, buttons, and the like. In other examples, input is received via soft input sources, such as software buttons, graphic user interface buttons, software setting toggles, and the like. In yet another example, the input is received by a user unplugging and plugging in the coupling between the first device and the second device. When the user does not want the second device to act as the source device, method 200 remains at operation 210 . When the user desires the second device to act as the source device, method 200 proceeds to operation 212 .

At operation 212, the second device enables the DRP functionality of the second device. In at least some examples, enabling the DRP feature will cause the second device to have Rd present on the CC line when the first device (or another device coupled to the second device) has Rd present on the CC line. device to have Rp present on the CC line and to begin operating as a source device to recharge the first device. After enabling the DRP feature, method 200 proceeds to operation 214 . Alternatively, when the second device did not disable the DRP feature in operation 208 and instead inhibited power transfer, in operation 212 the second device responds to the power transfer tolerance imposed in operation 208. Remove restrictions.

Returning now to operation 206, when Rd is not detected within a predetermined period of time, it indicates that the first device has been discharged and isolated from the second device, but operates as the first device, or sink device. Another device may indicate that it is coupled to the second device. In such an example, method 200 proceeds to operation 214 .

At operation 214, the second device begins sourcing power to the device (which may be the first device) that is coupled to the second device and has Rd present. In at least some examples, the second device sources power via the DRP that previously received power from the first device before Rp is no longer detected in operation 202 .

Turning now to FIG. 3, an exemplary pseudocode table 300 for implementing power transfer is shown. In at least some examples, execution of the pseudocode shown in table 300 implements at least some operations of method 200 . The pseudocode of table 300 is, in at least some examples, a microprocessing unit such as microprocessing unit 114 of FIG. 1 when the microprocessing unit is implemented within a sink device, as described elsewhere herein. Implemented by a processing unit.

Table 300 shows the calculation routines for RpConnectionDetected, RpDisconnectDetected, and DisconnectHandler. In at least some examples, the routines shown in table 300 are part of another software program or process, such that the routines of table 300 are subroutines of a software program or process called by the software program or process. . For example, when a software program or process receives an input signal indicating that Rp has been detected, the software program or process calls the RpConnectionDetected routine and sets the variable RpLossSignal to false. Similarly, when a software program or process receives an input signal indicating that Rp is no longer detected, the software program or process calls the RpDisconnectDetected routine and sets the variable RpLossSignal to true. Additionally, as shown in Table 300, the RpDisconnectDetected routine calls the DisconnectHandler routine as a result of failure to detect Rp. In another example, after setting RpLossSignal to true, the RpDisconnectDetected routine returns to the software program or process that called the RpDisconnectDetected routine, which in turn calls the DisconnectHandler routine.

As indicated in the DisconnectHandler routine, after Rp disconnection is detected, the DRP functionality is disabled by calling the routine DisableDRPConfiguration. After disabling the DRP feature, the variable DisconnectTimeOut is initialized to zero, and as long as RpLossSignal remains true, until 200 ms has elapsed or the user provides input to override the timer delay, as a timer delay. Incremented by 1 unit per ms. For example, a user may indicate that a device implementing the pseudocode of table 300 should act as a source device (cause the variable OperateAsSourceDevice to have a value of true as set by another routine or subroutine). When indicated, the DisconnectHandler stops incrementing the counter and enables the DRP function. Additionally, in some examples, the DisconnectHandler stops incrementing the counter and enables the DRP functionality when 200 ms has passed since the DisconnectTimeOut initialization. In at least some examples, DRP functionality is enabled by calling the routine EnableDRPConfiguration.

Although table 300 shows pseudocode including certain variables, operations, functions, and process flows, various other programming implementations of method 200 exist. The pseudocode for table 300 is not intended to exclude these other programming implementations from the scope of this disclosure. Instead, the pseudocode of table 300 merely illustrates one exemplary implementation while retaining other programming implementations of method 200 within the scope of this disclosure.

Turning now to FIGS. 4A and 4B, flowcharts of exemplary methods for controlling power transfer are shown. In at least some examples, the method is implemented by a pair of devices coupled together via a DRP, one acting as the source device and one acting as the sink device. . For example, the method performs microprocessing in a first device operating as a source device, initially operating as a sink device, but later changing roles to provide power to a second device operating as a source device. At least partially implemented by a microprocessing unit such as unit 114 . The method is also implemented at least partially by another microprocessing unit, such as microprocessing unit 114, in the second device. In at least some particular examples, the method is implemented in a source device, such as source device 102 described above with respect to FIG. 1, and a sink device, such as sink device 106 also described above with respect to FIG. implemented in part by a microprocessing unit such as

For example, the method includes first portion 405 and second portion 410 . The first portion 405 is, in at least some examples, implemented in a first device that initially acts as a source device. The second portion 410 is, in at least some examples, implemented in a second device that initially acts as a sink device. In operation 415, the first device determines whether the residual charge on the power supply of the first device is less than about 5% of maximum capacity. The first portion 405 remains in operation 415 when the residual charge is not less than 5% of the maximum capacity. When the residual charge is less than 5% of the maximum capacity, the first portion proceeds to operation 420 . In other examples, the alert message is sent based on another threshold of residual charge, such as about 10%, about 20%, about 2%, or any other suitable amount of residual charge. In at least some examples, the alert message is sent based on the rate of discharge of the power supply of the first device such that the alert message is sent with a particular amount of charge time remaining at a particular current draw. (eg, a warning message is sent about 5 minutes before charging ends). In at least some examples, the alert message is or is sent as a component of a PD message.

At operation 420, the first device transmits an alert message. In at least some examples, the alert message includes the status of the first device and indicates residual charge on the power supply of the first device. For example, in some implementations the power supply for the first device is a battery and the status of the first device indicates the remaining charge in the battery. The alert message, in at least some examples, is transmitted to the second device when the second device is coupled to the first device and receives power from the first device.

At operation 425, the second device receives the alert message. In at least some examples, the alert message is received from the first device. For example, in at least some implementations, the alert message received at act 425 is the alert message sent by the first device at act 420 . In another example, the alert message received by the second device at operation 425 is received from any suitable source, the scope of which is not limited herein, and the second part 410 of the method possible and independent of the first part 405 of the method. In at least some examples, the alert message indicates the status of the device acting as the source device to provide power to the second device. For example, conditions include residual charge in the power supply of a source device such as a battery.

At operation 430, the second device disables the DRP functionality of the second device. In at least some examples, disabling the DRP feature means that when the first device has Rd present on the CC line, the second device will It prevents the presence of Rp on the coupling CC line and starting operation as a source device to recharge the first device. Alternatively, in at least some examples, instead of disabling the DRP feature in operation 430, the second device limits the allowable rate of power transfer such that power transfer is inhibited, but not completely prevented. do.

At operation 435, the second device determines whether the user wants the second device to act as the source device. The second device, in at least some examples, makes decisions based on input received from the user. In some examples, input is received via physical, articulable input sources such as switches, toggles, buttons, and the like. In other examples, input is received via soft input sources, such as software buttons, graphic user interface buttons, software setting toggles, and the like. When the user does not want the second device to act as the source device, the first part 410 of the method remains at operation 435 . When the user desires the second device to act as the source device, the second part 410 of the method proceeds to operation 440 .

At operation 440, the second device enables the DRP functionality of the second device. In at least some examples, enabling the DRP feature will cause the second device to have Rd present on the CC line when the first device (or another device coupled to the second device) has Rd present on the CC line. device to have Rp present on the CC line and to begin operating as a source device to recharge the first device. Alternatively, when the second device does not disable the DRP feature in operation 430 and instead suppresses power transfer, in operation 440 the second device responds to the power transfer tolerance imposed in operation 430. Remove restrictions.

Turning now to FIG. 5, exemplary pseudocode tables 505 and 510 for implementing power transfer are shown. In at least some examples, execution of the pseudo-code shown in table 505 may perform at least some of the methods of FIGS. 4A and 4B, such as the operations included in first portion 405 of the methods of FIGS. 4A and 4B. implement behavior; Similarly, in at least some examples, execution of the pseudocode shown in table 510 may be performed at least in the methods of FIGS. 4A and 4B, such as the operations included in the second portion 410 of the methods of FIGS. Implement some behavior. In at least some examples, the pseudo-code of table 505 may be applied to a microprocessing unit, such as microprocessing unit 114 of FIG. 1, when the microprocessing unit is implemented within a source device, as described elsewhere herein. Implemented by a processing unit. In at least some examples, the pseudocode of table 510 may be used by a microprocessing unit, such as microprocessing unit 114 of FIG. 1, when the microprocessing unit is implemented within a sink device, as described elsewhere herein. Implemented by a processing unit.

As indicated by the pseudocode in table 505, the first device continuously monitors charge to determine if the charge level is below the alarm threshold. In at least some examples, the charge level is that of a power supply, such as a battery of the first device, and the alert threshold is a percentage of maximum charge remaining, an amount of time remaining to end charging, or any other suitable threshold. An alert message is sent when the charge level is below the alert threshold.

As indicated by the pseudocode in table 510, when the second device has not received an alert message, the second device will wait a predetermined time before returning to again determine if the alert message has been received. Call the Delay subroutine, which implements the delay for the duration. When the second device receives the alert message, the second device disables the DRP functionality by calling the routine DisableDRPConfiguration. After disabling the DRP feature, the second device monitors user input and delays until input is received. In some examples, the user input takes the form of user unplugging and replugging of the coupling between the first device and the second device. For example, when the user indicates that the second device should act as the source device (cause the variable OperateAsSourceDevice to have a value of true as set by another routine or subroutine), the second The device enables DRP functionality. In at least some examples, DRP functionality is enabled by calling the routine EnableDRPConfiguration.

Although tables 505 and 510 show pseudocode including certain variables, operations, functions, and process flows, various other programming implementations of Figures 4A and 4B exist. The pseudocode for tables 505 and 510 is not meant to exclude these other programming implementations from the scope of this disclosure. Rather, the pseudocode of tables 505 and 510 merely illustrate one exemplary implementation, while keeping other programming implementations of the methods of FIGS. 4A and 4B within the scope of this disclosure.

Turning now to FIG. 6, a flowchart of an exemplary method 600 for power transfer is shown. In at least some examples, method 600 is implemented by a microprocessing unit such as microprocessing unit 114 in either a source device such as source device 102 or a sink device such as sink device 106 .

At operation 602, power is transferred from the source device and the sink device. Power is transferred, for example, from a source device to a sink device. While power is transferred from the source device to the sink device, the source device is in the sourcing state or operating mode, terminating the coupling with the pull-up termination between the source device and the sink device. Similarly, while power is transferred from the source device to the sink device, the sink device is in a sinking state or operating mode, terminating the coupling with the pull-down termination between the source and sink devices.

At operation 604, power transfer from the sink device to the source device is inhibited. Power transfer is inhibited, in some examples, preventing power transfer, such as until user input is received commanding power transfer to occur. In another example, suppressing power transfer allows power transfer to occur, but reduces the transfer rate (eg, when compared to the transfer rate when not suppressed).

There are several suitable processes for suppressing power transfer. In at least one example, in one implementation, the source device sends an alert message to the sink device indicating charge remaining in the source device's power supply. Based at least in part on this alert message, the sink device inhibits reverse transfer of power from the sink device to the source device. Power transfer is inhibited, in at least some examples, until a timer expires and/or until user input is received. User input can include a user unplugging and replugging a connection between a source device and a sink device, a user pressing a hardware or software button, a user toggling a switch, and the like.

In another example, when the source device's power supply is depleted, the source device changes state of charge or changes mode from sourcing to sinking. This modification is accomplished by the source device removing the pull-up termination on the bond between the source and sink devices and providing a pull-down termination on the bond between the source and sink devices. . The sink device detects removal of the pullup termination and starts a timer. When the sink device detects pull-down termination of the coupling between the source and sink devices, the sink device suppresses power transfer back to the source device. For example, the sink device allows or prevents power transfer at a low rate. In at least some examples, suppression of power transfer continues until user input is received instructing the sink device to transfer power to the source device.

In the foregoing discussion, the terms "including" and "comprising" are used in an open-ended manner and should therefore be interpreted to mean "including but not limited to." The term "binding" is used throughout the specification. The term may encompass any connection, communication, or signal path that enables functional relationships consistent with the description of this disclosure. For example, if device A generates a signal to control device B to perform an action, then device A is coupled to device B in a first instance, or intervening device B in a second instance. Device A such that device B is controlled by device A via a control signal generated by device A when component C does not substantially change the functional relationship between device A and device B. is coupled to device B through an intervening component C. A device "configured to" perform a certain task or function may be configured (e.g., programmed and/or hardwired) at the time of manufacture by a manufacturer to perform that function, and/or It may be user configurable (or reconfigurable) after manufacture to perform functions and/or other additional or alternative functions. Such configuration may be accomplished through firmware and/or software programming of the device, through construction and/or layout of hardware components and interconnections of the device, or a combination thereof. Also, circuits or devices said to include certain components may instead be configured to combine those components to form the described circuit elements or devices. For example, one or more semiconductor elements (such as transistors), one or more passive elements (resistors, capacitors and/or inductors), and/or one or more sources (such as voltage and/or current sources). ) may alternatively contain only semiconductor elements within a single physical device (e.g., a semiconductor die and/or integrated circuit (IC) package), e.g., manufactured by an end user and/or a third party. It can be configured to bond to at least some of the passive elements and/or sources to form the described structures either at the point of manufacture or after the point of manufacture.

Although certain components are described herein as being of a particular process technology (e.g., FET, metal oxide semiconductor FET (MOSFET), n-type, p-type, etc.), these components replacing components of other process technologies (e.g., replacing FETs and/or MOSFETs with bipolar junction transistors (BJTs), replacing n-type with p-type or vice versa, etc.); , it is possible to reconfigure a circuit including the replaced components to provide desired functionality that is at least partially similar to functionality available prior to the component replacement. Components designated as resistors generally refer to any one or more elements coupled in series and/or parallel to provide the impedance quantity represented by the depicted resistor, unless otherwise specified. represents Additionally, use of the phrase "ground potential" in the discussion above may refer to chassis ground, ground, floating ground, virtual ground, digital ground, common ground, and/or ground potential as applicable or appropriate to the teachings of this disclosure. It is intended to include any other form of ground connection. Unless otherwise specified, "about," "approximately," or "substantially" preceding a value means +/−10 percent of the stated value.

The above discussion is meant to be illustrative of the principles and various examples of the present disclosure. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. The present disclosure is intended to embrace all such variations and modifications.

Claims (20)

a circuit,
a dual role port for transferring power to and from the circuit;
a microprocessing unit;
including
The microprocessing unit is
controlling the circuit to operate as a sink device for receiving power from a source device via the dual role port when the power supply includes a first amount of stored energy;
detecting a change in termination resistance of the source device at the dual role port;
controlling the circuit to limit power transfer from the circuit to the power supply through the dual role port when the power supply changes state from a sourcing state to a sinking state;
A circuit configured to 2. The circuit of claim 1, wherein to limit said power transfer, said microprocessing unit is configured to prevent power transfer from said circuit through said dual role port to said power supply. circuit. 2. The circuit of claim 1, wherein to limit said power transfer, said microprocessing unit outputs power from said circuit at a charge rate lower than the energy transfer rate at which said circuit received power from said power supply. A circuit configured to transfer power to the power supply. 2. The circuit of claim 1, wherein to limit said power transfer from said circuit to said power supply through said dual role port, said microprocessing unit further comprises:
receiving an alert message from the source device identifying residual charge on the power supply;
disabling the dual-role function of the dual-role port upon receiving the alert message;
monitor receipt of user input,
maintaining the disabled state of the dual role functionality of the dual role port unless otherwise indicated by the user input;
enabling the dual role functionality of the dual role port when the user input commands the circuit to operate as another source device;
configured to
circuit. 2. The circuit of claim 1, wherein the change in the status of the source device comprises disconnecting a pull-up termination from a communication line coupling the source device to the dual role port, and wherein the circuit A circuit configured to start a timer upon detecting said separation of the up termination. 6. The circuit of claim 5, wherein to limit said power transfer from said circuit to said power supply through said dual role port, said microprocessing unit further comprises
transferring power to the source device through the dual role port when a pull-down termination of the communication line coupling the source device to the dual role port is detected after expiration of the timer;
not transferring power to the source device through the dual role port when the pull-down termination of the communication line coupling the source device to the dual role port is detected prior to expiration of the timer;
configured to
circuit. 7. The circuit of claim 6, wherein the pulldown termination of the communication line coupling the source device to the dual role port is detected after expiration of the timer, causing the microprocessing unit to operate as another source device. A circuit, wherein the microprocessing unit is further configured to transfer power to the source device through the dual role port when commanding the circuit to do so. 2. The circuit of claim 1, wherein said dual role port is a Type C Universal Serial Bus and said circuit is at least part of a Type C Universal Serial Bus power transfer controller. a system,
including a power bank configured to operate as a source device;
the power bank
a battery;
dual role bus voltage terminals for transferring power to and from the battery;
a microprocessing unit;
including
The microprocessing unit is
controlling the battery to source power to a sink device via the dual role bus voltage terminals when the battery contains a first amount of stored energy;
inhibiting power transfer from the sink device to the battery through the dual role port when the battery contains less than the first amount of stored energy;
configured to
system. 10. The system of claim 9, wherein the microprocessing unit by transmitting an alert message to the sink device to cause the sink device to prevent power-carrying role reversal of the source device and the sink device. A system configured to inhibit the power transfer from a sink device to the battery through the dual role port. 10. The system of claim 9, wherein the microprocessing unit:
detecting the charge level of the battery;
ceasing power transfer from the battery to the sink device when the charge level of the battery drops to a threshold;
configured to suppress the power transfer from the sink device to the battery through the dual role port by
Discontinuing the power transfer from the battery to the sink device prevents the battery from being fully discharged, and preventing the battery from being fully discharged is the source device and the sink device. to prevent power delivery role reversal of
system. 10. The system of claim 9, wherein the dual role port is configured to operate at least partially as an input terminal for charging the battery and an output terminal for discharging the battery to the sink device. A system that is a Type C Universal Serial Bus port. 10. The system of Claim 9, wherein the microprocessing unit:
receiving user input specifying an operating mode of the source device;
to prevent a communication line coupling the source device to the sink device from being terminated with a pull-down signal on the source device side of the communication line when the operating mode of the source device is a sourcing mode. , controlling the switch; and
configured to suppress the power transfer from the sink device to the battery through the dual role port by
power passes from the battery to the sink device through the dual role port of the power bank in the sourcing mode;
system. 14. The system of claim 13, wherein the microprocessing unit determines that when the operating mode of the source device is a sinking mode, the communication line coupling the source device to the sink device is one of the communication lines. configured to control the switch to allow termination with the pull-down signal at the source device side, wherein in the sinking mode power is supplied from the sink device through the dual-role port of the circuit; A system over said source device. A tangible, non-transitory computer-readable storage medium containing instructions that, when implemented by a microprocessing unit, cause the microprocessing unit to:
causing a device communicatively coupled to said microprocessing unit to receive power from a source device via a dual role port capable of non-concurrent operation as both an input terminal and an output terminal, said source device terminating a communication channel coupling the source device and the dual role port to a pull-up signal on the source side of the communication channel while the source device is outputting power;
Detecting removal of the pull-up signal at the source side of the communication channel;
starting a timer when the removal of the pull-up signal is detected;
causing detection of a pull-down signal terminating the communication on the source side of the communication channel;
inhibiting power transfer to the source device via the dual role port when the pull-down signal is detected to terminate the communication on the source side of the communication channel prior to expiration of the timer;
let the
A tangible, non-transitory computer-readable storage medium. 16. The computer-readable storage medium of claim 15, wherein executing the program instructions further comprises detecting that the pull-down signal terminates the communication on the source side of the communication channel after expiration of the timer. A computer readable storage medium that, when enabled, causes the microprocessing unit to control the device to transfer power to the source device through the dual role port. 16. The computer-readable storage medium of claim 15, wherein executing the program instructions further causes the microprocessing unit to:
receiving user input commanding transmission of power to the source device through the dual role port;
transferring power to the source device via the dual role port regardless of the relationship between detection of the pull-down signal terminating the communication on the source side of the communication channel and expiration of the timer;
causing the device to be controlled such that
computer readable storage medium. 18. The computer readable storage medium of claim 17, wherein the user input further causes the device to transfer the power to the source device prior to expiration of the timer. 16. The computer-readable storage medium of claim 15, wherein executing the program instructions disables dual role functionality of the dual role port until expiration of the timer, thereby causing A computer readable storage medium that causes the microprocessing unit to control the device so as not to transfer power to the source device. 20. The computer readable storage medium of claim 19, wherein executing the program instructions further causes the microprocessing unit to enable dual role functionality of the dual role port after expiration of the timer. medium.

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